Process of producing fermentable sugars.



UNITED STATES PATENT OFFICE.

FRANCIS E. GALLAGHER, OF NEWTON', AND HARRY S. MORK, OF BOSTON, MASSACHU- SETTS, ASSIGNORS T0 STANDARD ALCOHOL COMPANY, OF NEW YORK, N. Y., A.

CORPORATION OF MAINE;

PROCESS OF PRODUCING FERMENTABLE SUGARS.

No Drawing.

dlesex arid (2.) Suffolk, and State of Massa chusetts, have invented certain new and useful Improvements in Processes of Producing F ermentable Sugars, of which the following is a specification.

This invention relates to the production of fermentable sugars from ligno cellulose,s uch as sawdust or wood-Waste. and from other cellulosic raw materials. According to the.

invention, the cellulosic material is subjected to hydrolysis in presence of the reaction products in dilute solution of sulfuric acid and a suitable chlorid.

The process may be carried out as follows; Sawdust, wood-waste or other cellulosic raw material, preliminarily freed, in case of res.- inous woods, from volatile hydrocarbons, is digested by means of steam under pressure in presence of dilute sulfuric and hydrochloric acids obtained by reacting with sulfuric acid upon a soluble chlorid. The digestion may be carried out under widely varying conditions, but it is preferred to conduct the operation in a closed digester, under a steam pressure of 60 to 135 pounds per square inch. According to the character of the raw materials and the conditions of the process, the maximum percentage of fermentable sugars may be attained in fifteen to sixty minutes. The sulfuric and hydrochloric acids may be present in molecular proportions, or with an excess of either component of the mixture.

Specification of Letters Patent? For example, one per cent. of sulfuric acid and one per. cent. of sodium chlorid yielded, after dlges- Patented May 12, 1914.

Application filed July 15, 1912. Serial No. 709,568.

tion with sawdust, an extract containing 28.2 per cent. of total solids and 25.8 per cent. of reducmg sugars. Similarly, a mixture of 1.5 per cent. of sulfuric acid and 1.5 percent. of calcium chlorid yielded an extract contaming 27 per cent. of total solids and 23.5 per cent. of reducing sugars.

A mixture of sulfuric acid and a soluble chlorid yields among its reaction products sulfuric and hydrochloric acids, because even If no excess of sulfuric acid is employed abo 'e the molecular equivalent of the soluble chlorid, the condition of equilibrium in dilute solutionis such that a portion of the sulfuric acid remains in a free and uncombined state, or in a condition in which it is able to exert a hydrolytic action equivalent to that of the acid in the freestate.

I claim:

1. In a process of producing fermentable' sugars from ligno-cellulose or other cellulosic material, the step which consists in digesting the mass under pressure in presence of the reaction products in dilute solution of sulfuric acid and a soluble chlorid of a metal. i I

2. Ina process of producing fermentable 'sugars from ligno-cellulose or other cellulosic material, the step which consists in digesting the mass under pressure in presence of the reaction products in dilute solution of sulfuric acid and sodium chlorid.

In testimony whereof, we aflix our signatures in presence of two witnesses.

IfRANCIS E. GA LAG ER. HARRY S. -MORK.

' \Yitnesses:

ARTHUR D. LITTLE, AMY MONTGOMERY. 

